WOOD PIPE FOR CONVEYING IRRIGATION WATER. 37 



In 1901 the National Sugar Manufacturing Co. at Sugar City, 

 Colo., built about 4 miles of fir pipe, which was covered by earth to 

 a depth of 2 to 4 feet. The one-half inch steel bands began to give 

 way after six years, more of them each succeeding year, causing fre- 

 quent breaks in the line and much annoyance, especially in winter. 

 In 1910 this line was rebanded with f-inch round, refined bar iron. 



A 24-inch fir pipe 3 miles long was built for the Pueblo (Colo.) 

 waterworks in 1904. This was banded with one-half inch soft steel 

 bands, buried from 1 to 3 J feet deep, a part in shale, and some in an 

 adobe loam soil. About seven or eight years later the bands began 

 to fail. Four thousand feet of this pipe was replaced in 1912, and 

 the remainder was taken up in 1913. 



The foregoing examples are all continuous stave pipes, but an in- 

 vestigation of the life of machine-banded pipe shows a like varia- 

 bility, the length of service being dependent altogether upon condi- 

 tions. Instances are frequently published illustrating the extremely 

 long life of the old bored log pipes which were used in the early 

 days, and there is probably a considerable amount of machine- 

 banded pipe which under favorable conditions has now been in use 

 for 30 years or more, while in a great many places the conditions of 

 service have been such as to render the life very short. 



A. F. Doremus, of Salt Lake City, Utah, states that flat-banded 

 bored pipe laid for the city water system of Tooele, Utah, in 1890 is 

 still generally in good condition, except in places where it was not 

 kept wet. This system now consists of about 20 miles of wood pipe, 

 much of which is of the modern machine-banded stave type. Some 

 of the modern pipe has had to be replaced in three years. A great 

 many instances might be cited where the life of machine-banded pipe 

 has been only from 4 to 10 years. Based upon the experience in 

 Spokane, Wash., the life of machine-banded wood pipe is given as 

 ranging from 4 to 12 years. 1 Such short life in most instances is 

 probably due to bad judgment in the matter of location or the use 

 of pipe under conditions altogether unfavorable to its life. 



Frequently in connection with municipal water systems pressures 

 are imposed far in excess of those for which the pipe was designed, 

 thus hastening its destruction. For irrigation systems the demand 

 by some of the promoting companies for an extremely cheap pipe 

 without particular consideration as to its durability has probably in 

 some instances led the manufacturers to incorporate poor material in 

 the pipe supplied. 



The unfavorable conditions of whatever nature, singly or together, 

 result most frequently in the decay of the pipe, thus shortening its 

 life. The decay of wood pipe is probably due primarily to the 



1 Ami. Rpt. Water Div., Dept. Public Utilities [Spokane, Wash.], 1911. 



